Improving the Energy Efficiency of Greenhouse Crop Production
Dr. Erik Runkle, Michigan State University, $20,000, 2 year project
Other Project Team Members -
Matthew Blanchard, Ph.D. candidate, Horticulture, Michigan State University
Dr. Jonathan Frantz, Research Horticulturist, USDA-ARS, Toledo University
Dr. Arthur Cameron, Professor, Horticulture, Michigan State University
Dr. Steve Harsh, Professor, Agricultural Economics, Michigan State University
Dr. A.J. Both, Associate Professor, Bioresource Engineering, Rutgers University
EXECUTIVE SUMMARY
In the United States, the majority of bedding plants are produced in greenhouses from January through May, when high energy inputs are required to maintain a desirable temperature. The cost of energy for greenhouse heating has increased by over 60% in the past 6 years, which has threatened the profitability of growers located in temperate climates. In an attempt to lower their heating bill, many greenhouse growers have decreased their growing temperature without knowing the effects on production timing, plant quality, or the economic consequences. Our preliminary data indicate that the total amount of energy required to grow a crop can actually increase at cooler temperatures because the production time is lengthened. In addition, lengthened production cycles reduce the number of successive crops produced each year, which requires allocating overhead costs to fewer crops. This project will generate research-based information so that greenhouse growers can optimize temperature and light while consuming the least amount of energy per crop. We postulate that the cost of plant production at cooler temperatures and low light levels is closely related to the rate of development, but species-specific data limits the scope and accuracy of the predictions. We are requesting funding for the last two years of a three year project. In the first year, we began experimentation with bedding plants to quantify how temperature and light influence crop timing and plant quality. In the final two years, we will (1) continue research to quantify how temperature and daily light integral influence plant development and crop quality of over 25 bedding plant species; (2) develop species-specific models that can predict growth and development responses in a wide range of growing environments; (3) incorporate crop models into the grower-friendly computer program Virtual Grower (developed by the USDA-ARS), which will estimate crop timing and energy consumption based on user-defined inputs; and (4) perform an economic analysis of how temperature and light influence crop timing, scheduling, and energy and overhead costs. We also plan to use this information in collaboration with Dr. Paul Fisher (Univ. of Florida) and Dr. John Erwin (Univ. of Minnesota) to develop decision-support tools to improve the predictability of flowering of annual bedding plant species. For further information contact Dr. Erik Runkle at runkleer@msu.edu
